MRI Excels at Detecting Wrist Ligament Tears

Posted by Admin on February 25, 2009

The most advanced magnetic resonance imaging (MRI) machine is nearly as effective as going in surgically to detect tears in wrist ligaments, according to a recent study.
The author of the paper in the American Journal of Roentgenology, Thomas Magee of Neuroskeletal Imaging in Merritt Island, Fla., examined the magnetic resonance (MR) wrist images of 300 patients at his community imaging service. The scans were performed with a so-called 3-Tesla MRI machine, which is twice the magnetic strength of the most common system, the 1.5-Tesla MRI.

Forty-nine of the 300 patients went on to have arthroscopy, a minimally invasive surgical procedure in which a small incision is made in the joint and a fiber-optic cable with a video lens and light source on the end is inserted to examine possible tissue damage. In addition, 35 of the arthroscopy candidates were examined with magnetic resonance arthography, a procedure in which a series of X-rays is taken of a joint, followed by an MRI scan that images the contrast fluid that's injected to produce the X-rays.

According to Magee, the MRI scans generated no false positives and detected most of the wrist ligament and cartilage tears later found by surgeons during arthroscopy. MRI was a bit less sensitive than MR arthrography, but generated fewer false positives. The analysis found: -- The 49 patients who had arthroscopy had a total of 51 tears, including 22 triangular fibrocartilage complex (TFCC) tears, 18 tears in the scapholunate (a ligament), and 11 tears in the lunatotriquetral (another ligament).

-- MRI detected 19 of the TFCC tears, 16 of the scapholunate tears, and nine of the lunatotriquetral tears. -- Compared with arthroscopy, MRI sensitivity was 86 percent for triangular fibrocartilage complex tears, 89 percent for scapholunate tears, and 82 percent for lunatotriquetral tears. -- There were no false positives. - Compared with surgery, MR arthrography sensitivity for detection of ligament and triangular fibrocartilage complex tears was 100 percent. However, there were three false positives.